"I realy like 'I Knew You Were Trouble,'" Underwood says. "It sounded a lot different for her. I liked the branching out, trying some different sounds."

As for how she thinks rumors of a riff between her and Swift even got started, the Grammy winner noted, "In every magazine, in pretty much every newspaper or on gossip TV shows, they can just get away with it by saying 'a source said' or 'an insider said.' I've read the most ridiculous things about myself when people do that."